Impacts of changing the ssb-periodicityServingCell

Dear Experts,
What will be the impact of changing the ssb-periodicityServingCell from 20msec to 5msec?
Will it impact coverage and SINR?

I guess coverage will not be impacted but SINR will be impacted specifically in high mobility case

Dear The Impact on SINR will be good or bad.
How will Impact scanner results?
Any reference?

Dear Brother
During beam sweeping one SS/PBCH block is transmitted using one beam in one direction and then the next block is transmitted to a different direction using a different beam and so on, thus effectively sending this broadcast information to all portions of the cell. just like below example(for Low band)
So the total time taken by the UE to get to an optimal beam pair is a function of the total beam sweeping time for UE receive beam and the “SS Block periodicity”.

Therefore, any optimization of periodicity time depends upon the above mentioned two factors(SSB periodicity and receive beam sweeping time) in turn, depends upon the number of beams, beam widths and the coverage area too.

For Mid/Low-band, SINR will not much be impacted as we have to transmit only 8/4 SSB beams within the ssb-burst(5ms). (Depends on vendor implementation/settings, we can see how many SSBs are tramsmitted in ssb-PositionsInBurst in rrc-reconfig message. (if 1000000 than only 1 SSB, 0110000 than 2 SSBs etc)
After 10 ms, again we can broadcast SSB instead of 20ms without any issue. Hope this will not impact SINR(but whether it improves SSB SINR not sure).

You can do the trial on few sites and update here about the SINR with how many SSB transmission.

But ensure to check B1 Measurement Gap related parameters(Like smtc duration,offset and periodicity from LTE side(Because E-NB and G-NB, both have to be aligned on BFN, bfnoffset parameter under REC(RadioEquipclock mo).

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